Refrigerated display case



June24y194L .LJ.BOOTH' REFRIGERATED DISPLAY CASE Filed Dec. 25

1 N VENT OR.

Patented June 24, 1941 UNITED STATES PATENT OFFICE 2,241,274 aarmcsnuan DISPLAY cnsn Jack J. Booth, Dallas, Tex. Application December 23, 1940, Serial No. 371,256

(Cl. sz-sasi 6 Claims.

This invention relates to refrigerating fixtures and equipment and it has particular reference to a refrigerated box especially adapted for storing and dispensing beverages and kindred merchandisc.

The principal object of the invention is to provide in a refrigerator of the character set forth, an improved air circulating system by which uniformity of temperature is maintained at all times throughout the fixture inasmuch'as provision is made for impelling currents of air downward toward and through a false bottom in the fixture as well as longitudinally therethrough. Hence, a part of the air in the act of returning to a point for recirculation through the refrigerating coils of the fixture, is caused it be drawn into intimate contact with the coil plate, thus holding the same at the lowest possible temperature.

Another and equally important object of the invention is to provide for the defrosting of the refrigerating coils without requiring the removal of the contents of the fixture or raising to any appreciable degree the temperature of the storage compartment of the fixture. It has been the practice to defrost the freezing coils of conven--v tional display cases by forcing a draft of pre-- heated air through the coils after first closing off the storage compartment of the fixture from the coil compartment. Through the advantage gained by a return air duct clue to the provision of a louvered false floor, the invention enables a refrigerated fixture to be defrosted without an air heating means and defrosting can be quickly done without disturbing the contents of the fix ture or raising the temperature thereof to such a degree as-to be damaging or which would result in inefliciency of the fixture during the defrosting operation.

With the foregoing objects as paramount, the invention has particular reference to its salient features of construction and arrangement of parts which will become manifest as the description proceeds, taken in connection with'the accompanying drawing, wherein:

Figure 1 is a perspective view of a refrigerating fixture with portions broken away to illustrate the invention.

Figure 2 is a transverse section on line 2-2 on Figure 1.

Figure 3. is a "fragmentary view in vertical sectionof one end of the refrigerating fixture, and

Figure 4 is a detail fragmentary view in perspective of one of the defrosting doors and showing the relationship between the door and the means for diverting upwardly moving air currents.

Continuing with a more detailed description of thedrawing, the display case or refrigerating fixture as it has been previously called has insulated walls I 0 as well as an insulated top or counter II and an insulated floor l2. Midway between the ends of the case are compartments l3 for barreled merchandise having doors it, while on either side of these compartmentsare compartments for storing and displaying bottled merchandise I5 as well as other commodities which must be kept at low temperatures. These latter compartments are provided with sliding or lift-up type doors l6.

Since automatic refrigerating systems of the type herein employed are well known, only the evaporator coil I1 is illustrated and this coil is mounted between plates l8 extending substantially the full length of the case in the space I9 provided therefor.

Immediately above the space I 9 containing the evaporator coil isa passage or duct 20 which likewise extends substantially the full length of the case and is defined in effect, by plates 2|, removably supported to allow movement of air counter to the direction of flow through the evaporator compartment l9. These plates are louvered at 22 in such manner that free flow of air is not interfered with when moving in the predetermined direction, that is, toward the suction end of a blower 23, mounted in one end of the case. w

The blower 23 is operative at all times to establish and maintain artificial circulation of air toward one end of the case through the evaporator compartment l9, upward through the vertical end duct 24 (Figures 3 and 4), into the upper part 25 of the case as deflected by the baffle 26 (Figure 3) and while some of the air is diverted through the upper duct 21 (Figure 3), a part thereof, under influence of the blower 23, will be pulled downward through the merchandisc in compartments I3 and I5 and through the louvers 22 in the false floor 2|. That part of the air returning to the blower through the upper duct 21 will have the effect of further insulating the top of the case against external heat while the air diverted downward through the false fioor 2| will maintain a uniform temperature throughout the interior of the case and will return through the return duct 20 for recirculation as described. g

In order that accumulations of frost and ice may be removed from the coil to maintain its efliciency, defrosting doors 28 and 29 are provided at the ends of the case. In Figure 4 is shown the manner in which the air normally passing upward into the case through vertical duct 24 is stopped from so doing by a flap 30, operated by door 29, and diverted into the return duct 20 so that circulation of air will be confined to the evaporator chamber and return duct 20. Circulation of air is efiected through door 28, from outside of the box, through the evaporator compartment l9 and out through the door 29, with some air being diverted through the return duct 20 as described.

The relationship of door 29 with the flap 30 is shown in Figure 4. This flap 30 has an arm 3| attached thereto and against which the door 29 engages when the latter is closed, to raise the flap whereby to open the duct 24 to circula- -tion of air. When defrosting, however, the door 29 is opened and the flap, by its own weight, falls to a position to close the duct 24 against passage of air. A coiled spring 30 shown only in Figure 4 normally urges the flap 30 to closed position over duct 24.

At the opposite end of the case, a perforated baflle 32 (Figure 1) separates the storage compartment I from the blower 23, although allowing for passage of air through its perforations 33. With the duct 24 at the opposite end of the case closed by the fiap 30, circulation of air throughout the upper part of the case ceases while warm air entering through door 28 is passed through the coil compartment l9, defrosting the coil therein, to return through the return duct 20 for recirculation until such time as the accumulation of frost on the coil has been reduced to water and drained off. This requires but a few minutes and is accomplished without raising the temperature of the storage and dispensing compartmerits of the case but a negligible degree, insufficient to harm the merchandise in thecase.

It is apparent from the foregoing that by virtue of the false bottom or floor 2|, the return air duct 20 is defined, to insure uniformity of temperature throughout the case, and makes possible a defrosting operation without requiring removal of any of the articles of merchandise therefrom and accordingly, there will be no interruption of business while the case is being,

This eliminates any froien merchandise is also considered to be within the spirit and intent of the invention.

What is claimed is: V 1. In a refrigerated merchandise display case having insulated walls, top and bottom, means defining an air passage along the bottom of said tion of air normally through said first passage for return by downward deflection toward and through said first air duct and means for introducing external air into said case and confining the same for circulation through said first air passage and first air duct to defrost said coil.

2. A refrigerating display case having insulated walls, top and bottom, an air pasage in the bottom" of said case, a refrigerating coil disposed in said air passage, a horizontal air duct mounted above said coil and in contiguous relation thereto and having openings in its upper surface, a vertical air duct eifecting-communication between said air passage, horizontal air duct and upper portion of said case whereby air under forced circulation through said air passage will normally enter the said upper portion through said air passage and vertical duct to be drawn downward toward and through said horizontal air duct for recirculation, and means for introducing external air into said case and confining the same for circulation in said air passage and horizontal air duct at a temperature higher than that of the upper portion of said case for defrosting said coil.

3. A refrigerated display case having upper and lower compartments, said lower compartment being defined by a pair of air passages extending longitudinally in said case, one above the other, substantially the full length thereof, a refrigerating element disposed in the lowermost of said air passages, louvers in the top surface of the companion air passage, a vertical air duct effecting communication between said upper and lower compartments, means for forcibly circulating air through said lowermost air passage into said upper compartment, to be impelled downward therethrough and into said upper air passage for return and recirculation means for opening either end of said case for entrance of external air and means effective simultaneously with the opening of one end of said case to close said vertical air duct to constrain said external air to circulate only through said lower compartment to defrost said coil.

4. A refrigerating unit comprising an insulated case having a merchandise storage compartment and a cooling compartment therebelow said latter compartment containing air passages, one above the other, a refrigerating unit in the lower air passage, said upper passage having openings at spaced intervals throughout its length, means for forcing air through said lower passage from one end to the opposite end of said case and upward into said merchandise compartment whereby said air will be impelled downward through said merchandise to enter and return through said upper air passage, means for opening said air passages to the circulation of external air and for simultaneously confining said air thereto for defrosting said coil.

,5. A refrigerating unit comprising an insulated display case having a merchandise compartment and a cooling compartment in normal communication therewith, a refrigerating element'in such cooling compartment and through which air is constrained to flow longitudinally of said case, an air moving means, an air passage above said cooling element in which said air is moved in a direction counter to the flow of air through said cooling element and having openings in its upper. surface through which air is influenced to flow by said air moving means from said merchandlse compartment, means effective to intro- 6. A structure as set forth in claim 5 in which the air passage above the cooling element is defined by removable plates in contiguous relationship and arranged to support merchandise in the merchandise compartment.

JACK J-. BOOTH. 

